@article{StollenwerkReinkensmeierGeorgetal.2021,
  author    = {Stollenwerk, Dominik and Reinkensmeier, Sebastian and Georg, J{\"o}rg Heiner and Jungbluth, Christian},
  title     = {„Smartes" Laden an {\"o}ffentlich zug{\"a}nglichen Lades{\"a}ulen - Teil 2: USER-Verhalten und -Erwartungen},
  series = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  volume    = {71},
  journal   = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  number    = {3},
  publisher = {ETV Energieverlag},
  address   = {Essen},
  isbn      = {0720-6240},
  issn      = {0013-743X},
  pages     = {38 -- 42},
  year      = {2021},
  language  = {de}
}
@article{ButenwegKubalskiElDeibetal.2021,
  author    = {Butenweg, Christoph and Kubalski, Thomas and El-Deib, Khaled and Gellert, Christoph},
  title     = {Erdbebennachweis von Mauerwerksbauten nach DIN EN 1998-1/NA-2021},
  series = {Bautechnik : Zeitschrift f{\"u}r den gesamten Ingenieurbau},
  volume    = {98},
  journal   = {Bautechnik : Zeitschrift f{\"u}r den gesamten Ingenieurbau},
  number    = {11},
  editor    = {Jesse, Dirk},
  publisher = {Ernst \& Sohn},
  address   = {Berlin},
  issn      = {1437-0999},
  doi       = {10.1002/bate.202100064},
  pages     = {852 -- 863},
  year      = {2021},
  abstract  = {Mauerwerksbauten in Deutschland sind mit Einf{\"u}hrung des nationalen Anwendungsdokuments DIN EN 1998-1/NA auf Grundlage einer neuen probabilistischen Erdbebenkarte nachzuweisen. F{\"u}r erfolgreiche Erdbebennachweise {\"u}blicher Grundrissformen von Mauerwerksbauten stehen in dem zuk{\"u}nftigen Anwendungsdokument neue rechnerische Nachweism{\"o}glichkeiten zur Verf{\"u}gung, mit denen die Tragf{\"a}higkeitsreserven von Mauerwerksbauten in der Baupraxis mit einem {\"u}berschaubaren Aufwand besser in Ansatz gebracht werden k{\"o}nnen. Das Standardrechenverfahren ist weiterhin der kraftbasierte Nachweis, der nun mit h{\"o}heren Verhaltensbeiwerten im Vergleich zur DIN 4149 durchgef{\"u}hrt werden kann. Die h{\"o}heren Verhaltensbeiwerte basieren auf der besseren Ausnutzung der geb{\"a}udespezifischen Verformungsf{\"a}higkeit und Energiedissipation sowie der Lastumverteilung der Schubkr{\"a}fte im Grundriss mit Ansatz von Rahmentragwirkung durch Wand-Deckeninteraktionen. Alternativ dazu kann ein nichtlinearer Nachweis auf Grundlage von Pushover-Analysen zur Anwendung kommen. Vervollst{\"a}ndigt werden die Regelungen f{\"u}r Mauerwerksbauten durch neue Regelungen f{\"u}r nichttragende Innenw{\"a}nde und Außenmauerschalen. Der vorliegende Beitrag stellt die Grundlagen und Hintergr{\"u}nde der neuen rechnerischen Nachweise in DIN EN 1998-1/NA vor und demonstriert deren Anwendung an einem Beispiel aus der Praxis.},
  language  = {de}
}
@article{ElDeibButenwegKlinkel2021,
  author    = {El-Deib, Khaled and Butenweg, Christoph and Klinkel, Sven},
  title     = {Erdbebennachweis von Mauerwerksbauten mit realistischen Modellen und erh{\"o}hten Verhaltensbeiwerten},
  series = {Mauerwerk},
  volume    = {2021},
  journal   = {Mauerwerk},
  number    = {3},
  editor    = {Jesse, Dirk},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1437-1022},
  doi       = {10.1002/dama.202110014},
  pages     = {110 -- 119},
  year      = {2021},
  abstract  = {Die Anwendung des linearen Nachweiskonzepts auf Mauerwerksbauten f{\"u}hrt dazu, dass bereits heute Standsicherheitsnachweise f{\"u}r Geb{\"a}ude mit {\"u}blichen Grundrissen in Gebieten mit moderaten Erdbebeneinwirkungen nicht mehr gef{\"u}hrt werden k{\"o}nnen. Diese Problematik wird sich in Deutschland mit der Einf{\"u}hrung kontinuierlicher probabilistischer Erdbebenkarten weiter versch{\"a}rfen. Aufgrund der Erh{\"o}hung der seismischen Einwirkungen, die sich vielerorts ergibt, ist es erforderlich, die vorhandenen, bislang nicht ber{\"u}cksichtigten Tragf{\"a}higkeitsreserven in nachvollziehbaren Nachweiskonzepten in der Baupraxis verf{\"u}gbar zu machen. Der vorliegende Beitrag stellt ein Konzept f{\"u}r die geb{\"a}udespezifische Ermittlung von erh{\"o}hten Verhaltensbeiwerten vor. Die Verhaltensbeiwerte setzen sich aus drei Anteilen zusammen, mit denen die Lastumverteilung im Grundriss, die Verformungsf{\"a}higkeit und Energiedissipation sowie die {\"U}berfestigkeiten ber{\"u}cksichtigt werden. F{\"u}r die rechnerische Ermittlung dieser drei Anteile wird ein nichtlineares Nachweiskonzept auf Grundlage von Pushover-Analysen vorgeschlagen, in denen die Interaktionen von W{\"a}nden und Geschossdecken durch einen Einspanngrad beschrieben werden. F{\"u}r die Bestimmung der Einspanngrade wird ein nichtlinearer Modellierungsansatz eingef{\"u}hrt, mit dem die Interaktion von W{\"a}nden und Decken abgebildet werden kann. Die Anwendung des Konzepts mit erh{\"o}hten geb{\"a}udespezifischen Verhaltensbeiwerten wird am Beispiel eines Mehrfamilienhauses aus Kalksandsteinen demonstriert. Die Ergebnisse der linearen Nachweise mit erh{\"o}hten Verhaltensbeiwerten f{\"u}r dieses Geb{\"a}ude liegen deutlich n{\"a}her an den Ergebnissen nichtlinearer Nachweise und somit bleiben {\"u}bliche Grundrisse in Erdbebengebieten mit den traditionellen linearen Rechenans{\"a}tzen nachweisbar.},
  language  = {de}
}
@article{MarinkovicButenweg2022,
  author    = {Marinkovic, Marko and Butenweg, Christoph},
  title     = {Numerical analysis of the in-plane behaviour of decoupled masonry infilled RC frames},
  series = {Engineering Structures},
  volume    = {272},
  journal   = {Engineering Structures},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0141-0296},
  doi       = {10.1016/j.engstruct.2022.114959},
  pages     = {18 Seiten},
  year      = {2022},
  abstract  = {Damage of reinforced concrete (RC) frames with masonry infill walls has been observed after many earthquakes. Brittle behaviour of the masonry infills in combination with the ductile behaviour of the RC frames makes infill walls prone to damage during earthquakes. Interstory deformations lead to an interaction between the infill and the RC frame, which affects the structural response. The result of this interaction is significant damage to the infill wall and sometimes to the surrounding structural system too. In most design codes, infill walls are considered as non-structural elements and neglected in the design process, because taking into account the infills and considering the interaction between frame and infill in software packages can be complicated and impractical. A good way to avoid negative aspects arising from this behavior is to ensure no or low-interaction of the frame and infill wall, for instance by decoupling the infill from the frame. This paper presents the numerical study performed to investigate new connection system called INODIS (Innovative Decoupled Infill System) for decoupling infill walls from surrounding frame with the aim to postpone infill activation to high interstory drifts thus reducing infill/frame interaction and minimizing damage to both infills and frames. The experimental results are first used for calibration and validation of the numerical model, which is then employed for investigating the influence of the material parameters as well as infill's and frame's geometry on the in-plane behaviour of the infilled frames with the INODIS system. For all the investigated situations, simulation results show significant improvements in behaviour for decoupled infilled RC frames in comparison to the traditionally infilled frames.},
  language  = {en}
}
@article{ButenwegMarinkovicPhlippetal.2022,
  author    = {Butenweg, Christoph and Marinkovic, Marko and Phlipp, Michel and Lins, Robin and Renaut, Philipp},
  title     = {Isolierung und BIM-basiertes Bauwerksmonitoring des neuen Geb{\"a}udekomplexes f{\"u}r das BioSense-Institut in Novi Sad, Serbien},
  series = {Bauingenieur},
  volume    = {97},
  journal   = {Bauingenieur},
  number    = {6},
  editor    = {Haghsheno, Shervin},
  publisher = {VDI Fachmedien},
  address   = {D{\"u}sseldorf},
  issn      = {1436-4867},
  doi       = {10.37544/0005-6650-2022-06-28},
  pages     = {S3 -- S5},
  year      = {2022},
  abstract  = {Im Norden von Serbien erfolgt in Novi Sad der Neubau eines modernen Forschungsgeb{\"a}udes f{\"u}r das BioSense-Institut mit finanzieller Unterst{\"u}tzung durch die Eu-rop{\"a}ische Union. Der Geb{\"a}udeteil mit Laboren wird zum Schutz und zur Sicherstellung des reibungslosen Betriebs der sensiblen und kapitalintensiven technischen Einbauten mit ei-ner Erdbebenisolierung mit integrierter K{\"o}rperschallisolation versehen. Zus{\"a}tzlich wird der entkoppelte Laborteil des For-schungsgeb{\"a}udes mit einem BIM-basierten Bauwerksmonito-ring versehen, um {\"A}nderungen des Geb{\"a}udezustands jederzeit abfragen und beurteilen zu k{\"o}nnen.},
  language  = {de}
}
@article{RossiWinandsButenweg2022,
  author    = {Rossi, Leonardo and Winands, Mark H. M. and Butenweg, Christoph},
  title     = {Monte Carlo Tree Search as an intelligent search tool in structural design problems},
  series = {Engineering with Computers : An International Journal for Simulation-Based Engineering},
  volume    = {38},
  journal   = {Engineering with Computers : An International Journal for Simulation-Based Engineering},
  number    = {4},
  editor    = {Zhang, Jessica},
  publisher = {Springer Nature},
  address   = {Cham},
  issn      = {1435-5663},
  doi       = {10.1007/s00366-021-01338-2},
  pages     = {3219 -- 3236},
  year      = {2022},
  abstract  = {Monte Carlo Tree Search (MCTS) is a search technique that in the last decade emerged as a major breakthrough for Artificial Intelligence applications regarding board- and video-games. In 2016, AlphaGo, an MCTS-based software agent, outperformed the human world champion of the board game Go. This game was for long considered almost infeasible for machines, due to its immense search space and the need for a long-term strategy. Since this historical success, MCTS is considered as an effective new approach for many other scientific and technical problems. Interestingly, civil structural engineering, as a discipline, offers many tasks whose solution may benefit from intelligent search and in particular from adopting MCTS as a search tool. In this work, we show how MCTS can be adapted to search for suitable solutions of a structural engineering design problem. The problem consists of choosing the load-bearing elements in a reference reinforced concrete structure, so to achieve a set of specific dynamic characteristics. In the paper, we report the results obtained by applying both a plain and a hybrid version of single-agent MCTS. The hybrid approach consists of an integration of both MCTS and classic Genetic Algorithm (GA), the latter also serving as a term of comparison for the results. The study's outcomes may open new perspectives for the adoption of MCTS as a design tool for civil engineers.},
  language  = {en}
}
@article{CheenakulaHoffstadtKrafftetal.2022,
  author    = {Cheenakula, Dheeraja and Hoffstadt, Kevin and Krafft, Simone and Reinecke, Diana and Klose, Holger and Kuperjans, Isabel and Gr{\"o}mping, Markus},
  title     = {Anaerobic digestion of algal-bacterial biomass of an Algal Turf Scrubber system},
  series = {Biomass Conversion and Biorefinery},
  volume    = {13},
  journal   = {Biomass Conversion and Biorefinery},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {2190-6823},
  doi       = {10.1007/s13399-022-03236-z},
  pages     = {15 Seiten},
  year      = {2022},
  abstract  = {This study investigated the anaerobic digestion of an algal-bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal-bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4\%) and a mixture of manure and maize silage (107.4\%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6\%) and percolated green waste (43.5\%) inocula. To further evaluate the potential of algal-bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7-12.5 MWh a-1) can be gained through the addition of algal-bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.},
  language  = {en}
}
@article{MorandiButenwegBreisetal.2022,
  author    = {Morandi, Paolo and Butenweg, Christoph and Breis, Khaled and Beyer, Katrin and Magenes, Guido},
  title     = {Latest findings on the behaviour factor q for the seismic design of URM buildings},
  series = {Bulletin of Earthquake Engineering},
  volume    = {20},
  journal   = {Bulletin of Earthquake Engineering},
  number    = {11},
  editor    = {Ansal, Atilla},
  publisher = {Springer Nature},
  address   = {Cham},
  issn      = {1573-1456},
  doi       = {10.1007/s10518-022-01419-7},
  pages     = {5797 -- 5848},
  year      = {2022},
  abstract  = {Recent earthquakes as the 2012 Emilia earthquake sequence showed that recently built unreinforced masonry (URM) buildings behaved much better than expected and sustained, despite the maximum PGA values ranged between 0.20-0.30 g, either minor damage or structural damage that is deemed repairable. Especially low-rise residential and commercial masonry buildings with a code-conforming seismic design and detailing behaved in general very well without substantial damages. The low damage grades of modern masonry buildings that was observed during this earthquake series highlighted again that codified design procedures based on linear analysis can be rather conservative. Although advances in simulation tools make nonlinear calculation methods more readily accessible to designers, linear analyses will still be the standard design method for years to come. The present paper aims to improve the linear seismic design method by providing a proper definition of the q-factor of URM buildings. These q-factors are derived for low-rise URM buildings with rigid diaphragms which represent recent construction practise in low to moderate seismic areas of Italy and Germany. The behaviour factor components for deformation and energy dissipation capacity and for overstrength due to the redistribution of forces are derived by means of pushover analyses. Furthermore, considerations on the behaviour factor component due to other sources of overstrength in masonry buildings are presented. As a result of the investigations, rationally based values of the behaviour factor q to be used in linear analyses in the range of 2.0-3.0 are proposed.},
  language  = {en}
}
@article{SchwagerFleschSchwarzboezletal.2022,
  author    = {Schwager, Christian and Flesch, Robert and Schwarzb{\"o}zl, Peter and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e}},
  title     = {Advanced two phase flow model for transient molten salt receiver system simulation},
  series = {Solar Energy},
  volume    = {232},
  journal   = {Solar Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0038-092X (print)},
  doi       = {10.1016/j.solener.2021.12.065},
  pages     = {362 -- 375},
  year      = {2022},
  abstract  = {In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed.},
  language  = {en}
}
@article{SchuellerRuhlDinstuehlerSengeretal.2022,
  author    = {Sch{\"u}ller-Ruhl, Aaron and Dinst{\"u}hler, Leonard and Senger, Thorsten and Bergfeld, Stefan and Ingenhag, Christian and Fleischhaker, Robert},
  title     = {Direct fabrication of arbitrary phase masks in optical glass via ultra-short pulsed laser writing of refractive index modifications},
  series = {Applied Physics B},
  volume    = {128},
  journal   = {Applied Physics B},
  number    = {Article number: 208},
  editor    = {Mackenzie, Jacob},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-0649 (Online)},
  doi       = {10.1007/s00340-022-07928-2},
  pages     = {1 -- 11},
  year      = {2022},
  abstract  = {We study the possibility to fabricate an arbitrary phase mask in a one-step laser-writing process inside the volume of an optical glass substrate. We derive the phase mask from a Gerchberg-Saxton-type algorithm as an array and create each individual phase shift using a refractive index modification of variable axial length. We realize the variable axial length by superimposing refractive index modifications induced by an ultra-short pulsed laser at different focusing depth. Each single modification is created by applying 1000 pulses with 15 μJ pulse energy at 100 kHz to a fixed spot of 25 μm diameter and the focus is then shifted axially in steps of 10 μm. With several proof-of-principle examples, we show the feasibility of our method. In particular, we identify the induced refractive index change to about a value of Δn=1.5⋅10-3. We also determine our current limitations by calculating the overlap in the form of a scalar product and we discuss possible future improvements.},
  language  = {en}
}